1. Field of the Invention
The invention is generally related to the storage and retrieval of data from streams, and in particular, to a manner of supporting multiple versions of a streaming protocol.
2. Description of Related Art
Streaming provides a mechanism for the storage and retrieval of persistent data in a computer system, or for the transmission of data between computer system modules, whether or not they are within the same computer system. With streaming, data is embedded in data streams that follow a predetermined streaming protocol to enable a module that receives a data stream to reliably decode and retrieve the data therefrom.
Many streaming protocols are designed to support the transmission of information between modules irrespective of their underlying hardware and/or software platforms. This is a particular concern with distributed and open computer systems, where computing tasks may be broken up and handled on multiple computers or multiple applications within a computer by passing objects between the computers or applications. With distributed systems, e.g., OMG's Common Object Request Broker Architecture (CORBA), IBM's Distributed System Object Component (DSOM), etc., often the underlying platforms may vary, and a module may not be able to direct data to a particular computer, or if it can, may not be able to detect the underlying platform of the receiving computer. Likewise, a module that formats an object for transmission to or use by another module in a separate application or computer may not be able to detect the particular application which will ultimately utilize the object, e.g., as with IBM's OpenDoc, Microsoft's Object Linking and Embedding (OLE), etc.
One concern that is raised with respect to such streaming protocols is that of release-to-release data compatibility. In particular, as computer systems and applications are upgraded, streaming protocols may likewise be upgraded to support enhanced functionality. The upgraded computer systems and applications, however, may still be required to communicate with computer systems and applications that only support earlier releases, or versions, of a streaming protocol. Likewise, the earlier versions may be required to communicate with computer systems and applications that support the newer versions. Since it is often difficult, if not impossible, to detect supported versions of a streaming protocol, some incompatibilities may occur.
Such incompatibilities may be eliminated by upgrading all computers and applications in a computer system to support the same streaming protocol, but this is often not feasible due to cost or control issues.
Therefore, a significant need exists for a manner of ensuring release-to-release data compatibility of streaming protocols within a computer system.